Interface-Engineered High-Performance Self-Powered Solar-Blind Photodetector Based on NiO/ε-Ga₂O₃ Heterojunctions

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Physics

Background:

• Self-powered solar-blind photodetectors are crucial for various applications.
• Gallium oxide (Ga₂O₃) heterojunctions offer potential but suffer from interface leakage current.
• This leakage compromises device sensitivity and response speed.

Purpose of the Study:

• To fabricate a novel NiO/ε-Ga₂O₃ p-n heterojunction solar-blind photodetector.
• To suppress interface leakage current and enhance device performance.
• To provide a new strategy for developing advanced Ga₂O₃-based optoelectronic devices.

Main Methods:

• Fabrication of a NiO/ε-Ga₂O₃ p-n heterojunction.
• Introduction of a high-resistance homogeneous layer at the heterojunction interface.
• Characterization of photodetector performance, including responsivity, detectivity, and response times.

Main Results:

• The NiO/ε-Ga₂O₃ photodetector successfully suppressed leakage current.
• The high-resistance layer extended the depletion region, improving carrier separation.
• Achieved notable responsivity (160 mA/W), detectivity (3.7 × 10¹² Jones), and fast response (38 ms rise, 67 ms decay) at zero bias.

Conclusions:

• The developed NiO/ε-Ga₂O₃ photodetector demonstrates superior performance compared to previous Ga₂O₃-based devices.
• The high-resistance interface layer is an effective strategy for mitigating leakage current.
• This work paves the way for advanced self-powered solar-blind photodetectors.